Browsing by Author "Resmy, V.R."

Now showing 1 - 4 of 4

Evolutionary Topology Optimization of Structural Concrete Under Various Load Cases
(Springer Science and Business Media Deutschland GmbH, 2021) Resmy, V.R.; C, C.
Topology optimization has wide applications in the field of engineering as it derives the optimum material layout in a given design space with defined loads and boundary conditions. This article presents the topology optimization of structural concrete with different load cases using a bidirectional evolutionary structural optimization method (BESO). BESO method has several advantages over other optimization methods as it removes inefficient elements and adds efficient elements in each iteration. The methodology adopts the compliance minimization with volume constraint by utilizing the capabilities of ABAQUS finite element software. Strut and Tie model (STM) has been identified as an effective method in modeling discontinuity regions in reinforced concrete structures as it can find out the real load transfer mechanism in structures. With the aid of topology optimization, all the uncertainties related to STM can be avoided. Â© 2021, Springer Nature Singapore Pte Ltd.
Stiffness maximization of concrete structures using topology optimization in static and dynamic problems
(Structural Engineering Research Centre, 2021) Resmy, V.R.; C, C.
This study highlights the generation of truss-like patterns for Strut and Tie Modeling (STM) using bidirectional evolutionary topology optimization in concrete structures. STM is an effective approach for the design of Discontinuity regions (D-regions) where standard Bernoulli’s hypothesis cannot be applied. As the conventional methods of STM generally follow a trial and error procedure, the final solution may not be unique. Topology optimization is classified under structural optimization to find the effective layout of structure based on the load path method. It is a scientific method that relies on structural mechanics; the inaccuracies related to STM can be avoided with the aid of topology optimization. In static problems, minimizing compliance leads to reasonably more stiff structures. In free vibration problems, the maximization of eigen frequency can be taken as an objective to get the maximum stiff structure. Solid Isotropic Material with Penalization (SIMP) material model assumes a constant and isotropic material properties in each discretized rectangular element. Evolutionary optimization derives the optimum structural layout by removing the ineffective elements and adding the effective elements in subsequent iterations. Method of Moving Asymptotes (MMA) developed by Svanberg (1997) is a kind of convex approximation has also been implemented in static problems. © 2021, Structural Engineering Research Centre. All rights reserved.
Topology Optimization of Concrete Beam Using Higher Order Finite Elements
(Springer Science and Business Media Deutschland GmbH, 2024) Resmy, V.R.; C, C.
Topology optimizations are based on the principle of eliminating solid material to ensure the efficiency of the design with an adequate amount of material. The optimized topology of a structure, the solution should have a clear distinction between solid and void that can be manufactured. The example problem taken in the present study for comparison is modeled with three different finite elements and optimized using three element updating algorithm. The Optimality Criteria (OC) method, Bidirectional evolutionary structural optimization (BESO) method, and Method of moving asymptotes (MMA) algorithm are used to update elements. Minimum compliance topology optimization with a prescribed volume fraction has been adopted for this study. The purpose of using higher-order elements is to check whether it change the optimum layout of the structure. Shape functions of higher-order elements can be derived by extra nodes on the sides of the linear element. BESO algorithm with 4-noded elements shows the fastest convergence with the least time. MMA algorithm with 9-noded elements takes the maximum computation time. Higher-order elements take a greater number of iterations to converge. The convergence history of different finite elements using the BESO algorithm has been checked. The optimum layout of structure in OC and MMA is almost similar in all order finite elements. Optimum topology using BESO method is similar for 8 and 9-noded elements. The fastest converged BESO algorithm shows a slight difference in optimum topology for higher-order elements. Solutions to optimization problems are simulated with a filter and without applying the filter. Higher-order elements extract the layout with less checkerboard pattern without a filter. Â© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.
Topology Optimization of Concrete Dapped Beams Under Multiple Constraints
(Springer, 2020) Resmy, V.R.; C, C.
Topology optimization is now becoming the effective method for solving various problems related to engineering. Optimization is a mathematical method to find the optimum solution by satisfying all the constraints associated with that problem, while topology optimization is a branch of structural optimization as it finds optimum material layout within the given boundary. This study focuses on the topology optimization of concrete dapped beams with various constraints to ensure the applicability of topology optimization during the design phase of structures. Compliance minimization with three different constraints along with volume constraint has been selected to derive the truss-like pattern for beams. To derive a lightweight structure with stress constraint, volume-based topology optimization has adopted. Strut-and-tie modeling (STM) of concrete members has been identified as a powerful method for modeling discontinuity regions within the structural member. Topology optimization can be used as a supporting method for developing more reliable strut-and-tie models. Â© Springer Nature Singapore Pte Ltd. 2020.